When a Florida couple goes missing, the discovery of a grisly bait freezer leads investigators through a precarious gauntlet involving a fishing boat, missing anchor, diamond ring and surprise informant who claims the truth is hidden at sea.

In the wake of a violent storm, a Rhode Island harbormaster finds a badly decomposed body aboard a sailboat. Now, detectives must uncover the truth: Was the killer Mother Nature or a more nefarious force?